Musk has offered to buy the company.

The boss of the two companies described his move as a "best and final offer" in a filing with the SEC.

I invested in the company because I believe in its potential to be the platform for free speech around the globe, and I believe free speech is a societal imperative for a functioning democracy, Musk wrote in a letter to the chairman.

In a letter to shareholders, Musk said that he believes the company should go private because it can't thrive and serve free speech.

He said that he was going to buy all of the company for $54.20 per share in cash, a 50% premium over the day before he invested.

If it is not accepted, Musk will need to reconsider his position as a shareholder.

The acquisition offer is certainly a realistic possibility since Musk is said to be worth around $230 billion. If he suddenly loses interest, he could abandon the proposal.

He made an offer and included a link to the filing in his early Thursday morning announcement.

A frequent critic of the platform, Musk recently acquired a 9.2% stake in the company, making him the company's largest shareholder.

He was offered a seat on the company's board after news of the stock purchase last week. He initially agreed to take it, but then declined at the last minute. He spent last weekend posting a series of now-deleted tweets about what changes he would like to see at the micro-blogging site. They included turning the San Francisco headquarters of the micro-blogging site into a homeless shelter. He suggested that a verification mark be added to users who sign up for the service.

On Tuesday, it was revealed that an investor was suing Musk, accusing him of costing shareholders money and failing to notify the SEC of his purchase in the required time frame.

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